They used to make them from Bosch 009 distributors, but I think those are finally out of production. The distributor is a bit too short and requires an extended gog (cannot be seen in the picture). The points were replaced with the Compufire 21100 module. For details, see the Compufire website.
I had mine modified by a guy that hops up VWs. All I had him do was to increase the total advance. I never bothered the springs as it seemed to work fine in my Alfetta.